>To test the equipment we did things like wrap 100m
>of the comms cable around a running DC lift motor and turned large motor
>contactors with the motors attached on and off.

I have seen similar things done to test for noise immunity, except the
device used was a small light box containing some fluorescent lamps. The
standard test was to plug this light box into the same mains outlet as the
equipment under test, and switch it on/off rapidly. If your equipment
faulted it did not have enough noise immunity.

As a footnote the light box had normal inductive ballasts, not the "no
ballast" design featured here for investigation recently. :)

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